Shipp, 22, is the biggest name in the group after captaining Notre Dame to the College Cup title last month. The striker compiled 12 goals and 10 assists in 24 matches during his senior season, earning ACC Offensive Player of the Year honors.

"Harry's a local guy, one of the best college players in the country and we are extremely excited to have him join the Fire," said new Fire coach Frank Yallop in a news release. "It speaks very highly of our player development system where a player of Harry's caliber can thrive and have a direct route to the first team. He's trained with the first team over the summer and we expect a smooth transition for him from the college game to the professional ranks."

Okoli, 20, joins Seattle after three campaigns at Wake Forest, making the All-ACC squad this past season as a forward. Kovar, 20, was a force in midfield over two seasons with Stanford, being named the Pac-12 Freshman of the Year in 2012.

Hamilton, a forward, represented Canada at the U-17 World Cup in the United Arab Emirates in October.